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如何在数据库中存储图像android [复制]

发布时间:2021-01-25 08:24:20 所属栏目:编程 来源:网络整理
导读:参见英文答案 How to save images into Database3个 我是android的新手,我正在创建一个联系人管理器.我已经研究了如何将EditText字段中的值存储到数据库中,但我不知道如何在数据库中存储图像.我想知道是否有人可以帮助我. package awad865.project.ContactMan

我的DatabaseHandler类:

package awad865.project.ContactManager1;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.sql.Blob;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.util.ByteArrayBuffer;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
import android.graphics.Bitmap;
import android.util.Log;

public class DatabaseHandler extends SQLiteOpenHelper {

    //declaring contants
    private static String DB_NAME = "ContactsDb";
    private static final int DB_VERSION = 1;
    private static String DB_PATH = "/data/data/awad865.project.ContactManager1/databases/";
    private final Context myContext;
    private SQLiteDatabase myDataBase;
    private static final String TABLE_CONTACT = "Contact";
    private static final String FIRST_NAME = "firstname";
    private static final String LAST_NAME = "lastname";
    private static final String NUMBER = "number";
    private static final String NUMBER_TYPE = "numbertype";
    private static final String EMAIL = "email";
    private static final String EMAIL_TYPE = "emailtype";
    private static final String DATE = "date";
    private static final String DATE_TYPE = "datetype";
    private static final String ADDRESS = "address";
    private static final String ADDRESS_TYPE = "addresstype";
    private static final String IMAGE = "image";
    private static final String FAVOURITE = "favourite";


    //the parent constructor is called
    public DatabaseHandler(Context context) {
        super(context,DB_NAME,DB_VERSION);
        this.myContext = context;
    }
    //method for creating the database
    public void createDataBase() throws IOException{
        boolean dbExist = checkDataBase();
        if(dbExist){
            //copyDataBase();
        }else{
            //By calling this method and empty database will be created into the default system path
            //of your application so we are gonna be able to overwrite that database with our database.
            this.getReadableDatabase();
            try {
                copyDataBase();
            } catch (IOException e) {
                throw new Error("Error copying database");
            }
        }
    }

    private boolean checkDataBase(){
        SQLiteDatabase checkDB = null;
        try{
            String myPath = DB_PATH + DB_NAME;
            checkDB = SQLiteDatabase.openDatabase(myPath,SQLiteDatabase.OPEN_READONLY);
        }catch(SQLiteException e){
            //database does't exist yet.
        }
        if(checkDB != null){
            checkDB.close();
        }
        return checkDB != null ? true : false;
    }

    private void copyDataBase() throws IOException{

        //Open your local database as the input stream
        InputStream myInput = myContext.getAssets().open(DB_NAME);
        // Path to the just created empty database
        String outFileName = DB_PATH + DB_NAME;
        //Open the empty database as the output stream
        OutputStream myOutput = new FileOutputStream(outFileName);
        //transfer bytes from the inputfile to the outputfile
        byte[] buffer = new byte[1024];
        int length;
        while ((length = myInput.read(buffer))>0){
            myOutput.write(buffer,length);
        }
        //Close the streams
        myOutput.flush();
        myOutput.close();
        myInput.close();

    }

    public void openDataBase() throws SQLException{
        //Open the database
        String myPath = DB_PATH + DB_NAME;
        myDataBase = SQLiteDatabase.openDatabase(myPath,SQLiteDatabase.OPEN_READONLY);
    }

    @Override
    public synchronized void close() {
        if(myDataBase != null)
            myDataBase.close();
        super.close();
    }
    //method for adding a contact to the database
    public void addContact(Contact contact) {
        SQLiteDatabase db = this.getWritableDatabase();
        ContentValues values = new ContentValues();
        //put all the appropriate edit text fields contact and store them in the database.
        values.put(FIRST_NAME,contact.getFirstName()); 
        values.put(LAST_NAME,contact.getLastName()); 
        values.put(NUMBER,contact.getNumber()); 
        values.put(NUMBER_TYPE,contact.getNumberType());
        values.put(EMAIL,contact.getEmail()); 
        values.put(EMAIL_TYPE,contact.getEmailType());
        values.put(ADDRESS,contact.getAddress()); 
        values.put(ADDRESS_TYPE,contact.getAddressType());
        values.put(DATE,contact.getDate()); 
        values.put(DATE_TYPE,contact.getDateType());
        values.put(FAVOURITE,"false");
        db.insert(TABLE_CONTACT,values);
        db.close(); // Closing database connection
    }

    // Deleting single contact
    public void deleteContact(String firstName,String lastName) {
        SQLiteDatabase db = this.getWritableDatabase();
        db.delete(TABLE_CONTACT,FIRST_NAME + "=? AND " + LAST_NAME + "=?",new String[] {firstName,lastName});
        db.close();
    }

    //this method is used for editing a contact
    public int updateContact(Contact contact,String firstName,String lastName) {
        SQLiteDatabase db = this.getWritableDatabase();
        ContentValues values = new ContentValues();
        //we first find the existing contact,and overwrite the old
        //values with the new values
        values.put(FIRST_NAME,contact.getLastName());
        values.put(NUMBER,contact.getFavourite());

        // updating row
        return db.update(TABLE_CONTACT,values,lastName});
    }

    public List<Contact> getFavouriteContacts() {
        List<Contact> contactList = new ArrayList<Contact>();
        String isFavourite = "true";
        // Select All Query
        String selectQuery = "SELECT * FROM " + TABLE_CONTACT + " WHERE " + FAVOURITE + "='" + isFavourite + "'";
        SQLiteDatabase db = this.getWritableDatabase();
        Cursor cursor = db.rawQuery(selectQuery,null);

        // looping through all rows and adding to list
        if (cursor.moveToFirst()) {
            do {
                Contact contact = new Contact(cursor.getString(0),cursor.getString(1),cursor.getString(2),cursor.getString(3),cursor.getString(4),cursor.getString(5),cursor.getString(6),cursor.getString(7),cursor.getString(8),cursor.getString(9),cursor.getString(11));
                // Adding contact to list
                contactList.add(contact);
            } while (cursor.moveToNext());
        }

        return contactList;
    }


    public Contact getContact(String firstName,String lastName) {
        List<Contact> contactList = new ArrayList<Contact>();
        // Select All Query
        String selectQuery = "SELECT * FROM " + TABLE_CONTACT + " WHERE " + FIRST_NAME + "='" + firstName + "' AND " + LAST_NAME + "='" + lastName + "'";
        SQLiteDatabase db = this.getWritableDatabase();
        Cursor cursor = db.rawQuery(selectQuery,cursor.getString(11));
                // Adding contact to list
                contactList.add(contact);
            } while (cursor.moveToNext());
        }

        return contactList.get(0);
    }




    public List<Contact> getContacts(String order) {
        List<Contact> contactList = new ArrayList<Contact>();
        // Select All Query
        //this bottom line is used to change the sorting order of the contact list
        String selectQuery = "SELECT * FROM " + TABLE_CONTACT +" ORDER BY " + order;
        SQLiteDatabase db = this.getWritableDatabase();
        Cursor cursor = db.rawQuery(selectQuery,cursor.getString(11));
                // Adding contact to list
                contactList.add(contact);
            } while (cursor.moveToNext());
        }
        return contactList;
    }

    @Override
    public void onCreate(SQLiteDatabase arg0) {
        // TODO Auto-generated method stub

    }


    @Override
    public void onUpgrade(SQLiteDatabase arg0,int arg1,int arg2) {
        // TODO Auto-generated method stub

    }

}

任何帮助,将不胜感激.提前致谢!

解决方法

最有可能你可以在你的数据库中使用BLOB,将图像转换为字节数组并存储在数据库中.

您还可以参考以下链接以获得公平和清晰的想法:

How to save images into Database.

How to store image in SQLite database

how to store Image as blob in Sqlite & how to retrieve it?

how to store and retrieve images in android SQLite database and display them on a gridview

how to save and retrive images from sql lite database in android

Android How to save camera images in database and display another activity in list view?

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